"I stand before you, I guess, with a whole new appreciation indeed for the god of second chances," he said.

Sanford's reelection to Congress was seen as a dramatic comeback, as he was forced to admit in 2009 to having an extramarital affair with an Argentine woman while governor of South Carolina. He alluded to that experience by saying his particular road back to Congress has made him more appreciative of the office he holds.

"Each one of our lives involve different journeys, but along that journey, I think that … we can, in essence, be taken to places when we develop levels of appreciation perhaps that we never had before," he said. "I stand here before each one of you more appreciative than I ever could have been for the honor of working with each one of you here in the United States Congress."

Sanford used his brief remarks to thank Rep. Eliot Engel (D-N.Y.) for offering his support "in the wake of the events of 2009."

"We're here today to recognize the survivor of the primary, the runoff and general election, Mark Sanford," Wilson quipped.

Sanford competed during much of the race without strong support from national leaders or the party.

Rep. James Clyburn (D-S.C.), the only Democrat from South Carolina, was not present today, but he prepared remarks that were read on the floor by Rep. David Price (D-N.C.).

"Swearing in is always about new beginnings," Clyburn's statement said. "In that spirit I want to extend the hand of collegiality to Mark Sanford as he begins a new chapter of service to the people of South Carolina and this great country in the U.S. House of Representatives.

"Though our past differences have been widely chronicled, and we bring different sets of experiences to the public square, I will always work to find common ground as we fulfill our duties and our responsibilities to the people who sent us here."

Looking on from the Speaker's gallery in the chamber, Sanford's fiancée, Argentine journalist Maria Belen Chapur, sat next to his two sons, Landon and Marshall. Sanford's sister, her husband and his parents also watched as he gave his first speech in 13 years on the House floor.

Minutes prior to his swearing in on the House floor, a number of GOP lawmakers approached their newest colleague with cautious smiles and cordial handshakes.

Sanford's colleagues from the Foreign Affairs Committee, where he served during his first round as a House member from 1995 to 2001 — greeted him with hearty handshakes and even a hug.

Rep. Dana Rohrabacher (R-Calif.), who served with Sanford on what was then called the International Relations Committee, embraced the new lawmaker with a big hug and back slap on the House floor.

For others, however, the greeting of the scandal-plagued South Carolinian seemed more perfunctory.

National Republican Congressional Committee Chairman Rep. Greg Walden (R-Ore.) appeared to exchange some pleasant words with Sanford, despite having pulled NRCC money from the South Carolina special election after revelations that Sanford had trespassed on his ex-wife's property, according to sealed court documents.